dr wogz
Fly caster
Fin cans are inherently strong with minimal adhesives. Over building fin cans is one of the more comical activities in this hobby.
and cue my comment from post #10 ....
Fin cans are inherently strong with minimal adhesives. Over building fin cans is one of the more comical activities in this hobby.
Good Post. Odd that this didn't show up yesterday.
Hi Jowayen,I prefer to use thin epoxy.
Before I place the rocket horizontally to dry, I like to run/pour/inject the epoxy down the root where the fillets will be.
I'll do 4 at a time, let dry, rotate 90 degrees and run epoxy down 4 more fillets... until completed.
I'm not extremely concerned about a "perfect" all-matching radii. It's just not that critical.
The purpose is to widen the bonding width of the adhesion surface.
Preparation of the surface is by far the most important step of the internal fillets.
View attachment 459097
Hi Jim! Thanks for your comment. Based on my experience, internal fillets are the first to give way, which would seem to indicate that they are a key stress point. I've been flying rockets for more than 65 years. Wildman voids his warranty if you don't have internal fillets. I'll keep the internal fillets.
Hi Jowayen,
I have this question about your method, please.
Does your thin epoxy, which you illustrate by means of the red dots, replace the fillets, or do you use the thin epoxy and then apply thicker epoxy to further build up the fillets?
Thank you.
Stanley
Yeah, this is a perennial question: how much is too much overbuilding? Since we don't know the exact properties of the materials we use nor the exact stresses they will encounter, we're always using our judgement. To me, skipping fillets to save time isn't not overbuilding, just taking a shortcut.
Enter your email address to join: